Aims Myeloid sarcoma (MS) is a rare extramedullary neoplasm composed of immature myeloid precursor cells thought to be a unique clinical presentation of acute myeloid leukaemia (AML). Like AML, MS has a poor prognosis, but due to the rare nature of MS there are limited studies examining potential prognostic factors. We report our institutional experience, with the aim of investigating and establishing salient clinicopathological and molecular features of MS. Methods and results We retrospectively examined all clinicopathological and molecular data on MS patients between 2001 and 2017 from the University of Alabama at Birmingham (UAB) electronic medical records. The UAB electronic medical records were also reviewed and compared with the literature for other potential prognostic factors. Sixty‐three patients were included in the study. The median overall survival was 24 months in the group with normal karyotype and 12 months in patients with an abnormal karyotype. Conclusions We found that an abnormal karyotype was associated with a statistically significant worse prognosis.

Carney Complex (CNC) is a rare autosomal dominant condition with characteristic clinical presentation, tumor development, and unique genetic mutation. We present a unique case and literature review of CNC in which two neoplasms characteristic of this complex were initially diagnosed through cytological fine needle aspirate specimens, leading to the identification of CNC, with subsequent surgical and cytogenetic confirmation. Diagn. Cytopathol. 2017;45:634-639. © 2017 Wiley Periodicals, Inc.

CD5 antigen expression in B-cell acute lymphoblastic leukemia (B-ALL) is exceptionally rare. There are six detailed case reports in the literature, with only 16 cases described. Case series analyzing the frequency of aberrant B-ALL immunophenotypes suggest that this variant may occur in as little as 2-4.5% of all B-ALL cases, with one series having no CD5 + positive cases. Herein we report a case of CD5 + B-ALL in a 15-year-old female, and review the previously reported cases. As limited information is available, more data from prospective clinical trials are required to determine whether CD5 positivity portends a poorer prognosis. K E Y W O R D S acute lymphoblastic leukemia, B-cell ALL, CD5 + , immunophenotypic aberrancies in ALL, variant B-ALL

Myeloproliferative neoplasms (MPN) associated with PDGFRA, PDGFRB, and FGFR1 rearrangements and formation of fusion gene encoding an aberrant tyrosine kinase constitute three rare distinct disease groups in the most current WHO 2008 classification. These diseases often share eosinophilia as a manifestation. Myeloid sarcoma (MS) is a rare form of myeloid neoplasms occurring in extramedullary sites. MS can develop de novo or concurrently with AML as an initial presentation or relapsed disease. We report a unique case of FIP1L1-PDGFRA fusion gene-positive MPN with initial clinical presentation as an intrathecal myeloid sarcoma. A 44-year-old man presented with an intrathecal mass compressing the spinal cord from vertebral segments C5-C6 to T3-T4 in 2008. He underwent an emergent laminectomy and the pathologic examination of excised tissue demonstrated features consistent with MS with eosinophilic cells as well as clusters of immature precursors and blasts staining with CD45 without expression of T-or B-cell markers. A bone marrow biopsy was subsequently performed along with flow cytometry and FISH analysis. The biopsy revealed a MPN with increased eosinophils. The myeloid cells coexpressed CD33, CD13, and CD15 without CD34 or CD117 via flow cytometry. The fluorescence in situ hybridization (FISH) testing confirmed FIP1L1-PDGFRA fusion gene due to interstitial deletion in4q12 region. A diagnosis of MPN with FIP1L1-PDGFRA was rendered. There was no evidence of transformation to acute leukemia or any other organ site involvement or tissue damage. He was started on Gleevec and subsequently received radiation therapy to the cervicothoracic spine. A FISH analysis approximately 2 months after initial testing and treatment with chemotherapy and radiation demonstrated absence of the FIP1L1-PDGFRA gene fusion. He remains well after 5 years. This case demonstrates a very unusual type of MS as the initial presentation of a rare form of chronic eosinophilic leukemia which has responded to tyrosine kinase inhibitor.